Gun barrel with breech piece screwed on a-tubes



J. VOLLMER. GUN BARREL WITH BREECH PIECE SCREWED 0N A-TUBES.

Patented Aug. 29, 1922.

w 1 7m m Guiana m I cesses 0i and 72 enclose a cylindrical hole a i or recess in which a cylindrical dowel F is uir PITENT orsica 301m VOLLMER, or, nssEN, GERMANY.

GUN BARREL WITH BBEECI'I PIECE SCREWED ON iii-TUBES.

Specification of lietters Patent. Patented ring. 29, 1922. Originalapplication filed November 19, 1920, Serial No. 425,105.

Divided and this application filed June 28, 1921. Serial No. 481,028.

To all whom itmag concern:

Be it known that 1, JOHN VoLLMER, residing at Essen, Germany, a citizen of the German Republic, have invented a certain new and useful Improvement in Gun Barrels with Breech Pieces Screwed on A-Tubes (for which I have filed an application in Germany June 2nd, 1921), of which the following is a specification.

This invention. relates to gun barrels having a breech-piece screwed upon the A-tube. The object of the invention is to provide means for attaining a rigid connection between the A-tube and breech-piece.

This application is a division of my copending application Serial No. 425,106 filed November 19th, 1920.

This invention relates particularly to means for obtaining this desired rigid connection with a breech-piece which envelopes only a small portion of the A-tube. The various features of this invention will be made more apparent in the accompanying specification and drawings in which:

Fig. l is a longitudinal section of a gun barrel and breech-piece constructed in accordance with this invention,

Fig. 2 is a section on line 22 of Fig. 1,

Fig. 3 is a plan view partly in section of the structure illustrated in Fig. l. and

Fig. 4: is a section of a detail on a larger scale.

The gun barrel consists of an A-tube A and a breech-piece B. this breech-piece being formed with a very short jacket portion 72 which envelopes the rear portion of the A tube. The breech-piece is provided on its under side with a lug for the attachment of a recoil brake and the running out gear. The connection liGtiVGGll the A-tube and the breech-piece is obtained by means of screwthreads a 7.? on the A-tuhe and breech-piece respectively.

The jacket portion 7) of the breech-piece B is provided with an annular extension 7), having the same outside diameter as the collar (film-med on the A-tube A. The collar (1 and the extension 79 are each provided on their opposite faces with six recesses a and 7): When the A-tube and breech-piece are assembled, the wall of each pair of reinserted.

The dowels F (see more particularly Fig.

4) are made of soft expansiblesteel. Each dowel F is perforated by an oval slot f' extended from oneendface f to the other, the generatrix ot the slot being parallel to the axis of the dowel. A double wedge formed by two wedges G Gr is adapted to be driven into this slot. The dowels F and the wedges G G are retained in position by a ring H fixed over the collar a and the extension 6 in any suitable manner, preferably by shrinking the same thereon.

The arrangement is applied in the following manner: After the breech-piece has been screwed on the A-tube the recesses a b are bored and the dowels F are placed in the recesses in such a manner that the oval slots 7 of some of the dowels assume the position shown in the drawing whereas the oval slots of the remaining dowels are placed at right angles thereto. Then the wedges G G are inserted in the dowels and driven tightly therein, thereby expanding the dowels and rigidly connecting the A-tube and the breechpiece. Finally the ring H is fixed over the collar a and the extension I).

This alternate arrangement of the dowels F and the wedges G G will prove a safeguard against the loosening of the breechpiece on the A-tube owing to the resistance set up by the recoil brake and the running out gear. It also prevents the loosening of the A-tube in the breechpiece, owing to the reaction of the rifling tending to rotate the A-tube. Furthermore, the cylindrical shape of the dowels F and the recesses a and b facilitates the exact machining of the parts in question and assures a uniform distribution of the pressure produced by the described wedge arrangement.

Having thus described my invention, what I claim is:

Claims:

1. A gun barrel comprising an A-tube, a breech-piece, said breech-piece being provided with an annular extension, said A- tube being provided with a collar, said annular extension and collar being opposed and shaped to receive a multiplicity of wedges.

2. A gun barrel comprising an A-tube, a breech-piece, said breech-piece being provided with an annular extension, said A tube being provided with a collar, the opposed faces of the annular extension and collar being shaped to provide recesses and an expanding means disposed in the hollow other, the-opposed faces thereof beingshaped-=- to form recesses and expansihle dowels:

space formed by the opposed recesses,

3. A gun barrel comprismg 'r'eech i iece,

an A-tube, said breech-piece. being rovided with an; annular extension, said A-tii e being formedwith a collar, said annular extension and collar being dis ose-"d adjacent one anadapted to be inserted in the spaces formed by. the opposed recessesand Wedges for e1 panding saiclcdowel's. 1 v

4; A gunbarr'el:comprising an "A-tn be 'a breech-pie'ce, "said breech-piece being pro-' vided with an annular extension, said A-tuhe being provided with a collar the opposed faces of the annular, extension and collar being shaped to provide recesses, expanding JOHN VOLLMER; 

